This invention concerns a new method of treating the syndrome of carbohydrate craving during which patients present an abnormal appetite for carbohydrate at definite hours.
At the present time, patients having a strong appetite for carbohydrate were not treated before appearance of obesity. At that stage, the use of compositions of large amounts of bulky substances or appetite-suppressant drugs have been utilized. The suppression of appetite was seen to result from a propensity to eat slower, to wait longer between meals or to stop eating sooner. Such drugs show no selectivity on the kind of feeding and have unwanted side effects such as induction of hyperactivity. Obese and even normal people often describe intense cravings for high-carbohydrate foods. These cravings tend to occur at characteristic times of day and are often enhanced by stress or, in women, by premenstrual tension. The carbohydrate foods consumed to satisfy these cravings range from sweet to starchy (e.g., ice cream, crackers), and thus seem to meet a common metabolic rather than sensory need. Carbohydrate consumption enhances brain serotonin synthesis (by eliciting insulin secretion, which changes the plasma amino acid patterns to facilitate brain tryptophan uptake); thus, carbohydrate cravings might, in some people, reflect inadequate serotoninergic neurotransmission. If so, then drug treatments designed to amplify serotonin release might ameliorate this appetite disorder.
A preferred method of treatment would involve the correction of the very nature of the feeding habits of some patients having an immoderate appetite for certain kinds of carbohydrate-containing food, particularly between meals. Such a state does not always entail obesity, but can indicate some metabolic disturbances or some neurotic troubles due to anxiety of becoming overweight.
Prior to the present invention, it has been known to administer d,1-fenfluramine or fluoxetine to an animal (rat) in order to selectively reduce consumption of carbohydrates while not significantly reducing consumption of protein. These results are shown by Wurtman et al, Science, vol. 198, pp. 1178-1180, December, 1977; Current Medical Research and Opinion, vol. 6, Suppl. 1, pp. 28-33, 1979 and Life Sciences, vol. 24, pp. 894-904, 1979.
D-fenfluramine and d,1-fenfluramine are known anorexic agents as disclosed in U.S. Pat. No. 3,198,834. However, prior to the present invention, neither d-fenfluramine nor d,1-fenfluramine has been known to selectively reduce carbohydrate craving which occurs in patients that have an abnormal appetite for carbohydrates at definite times.